Despite numerous investigations into the pathogenesis of non-insulin dependent diabetes (NIDDM), the primary metabolic, biochemical and molecular abnormalities responsible for insulin resistance, a characteristic feature, have yet to be elucidated. This is a portion of a larger study, "Regulation of Hepatic and Peripheral Glucose Metabolism." The purpose of this study is to relate insulin's effect in vivo to the basic biochemical and molecular events involved in the stimulation of muscle glucose phosphorylation and transport. In this sub-study, the effect of intensive insulin therapy on insulin sensitivity and insulin secretion will be studied. The effect of such intensive therapy on glucose phosphorylation and transport in subjects with NIDDM will be elucidated.